Boris Johnson was kept in the dark over some sensitive secret intelligence by Downing Street when he became foreign secretary, according to reports.
The BBC and The Sun newspaper, citing sources, claim the Tory leadership front-runner was not shown a category of information when he entered office in 2016.
He was said to have been aware of the decision at the time and “very unhappy” about it, but sources close to Mr Johnson denied the reports.
A source said there was no row about being denied access and that he saw everything he should have seen as foreign secretary.
A Downing Street spokesman said: “We do not comment on intelligence matters.”
The BBC, citing “multiple sources with direct knowledge of events” who are not involved in the leadership campaign or politics, reported Number 10 did not want Mr Johnson to be shown a category of sensitive secret intelligence.
The Sun claimed nerves were sparked when Mr Johnson was accused of revealing classified information by mistake.
A source told the paper: “The PM didn’t think Boris could be trusted because he had a loose tongue. He made the agencies anxious. He wasn’t told everything because of that.
“Pre-meetings would be arranged without his knowledge before he’d come over to No 10.
“They probably both share the blame for the situation, and it was a clash of their worst traits – Boris is a big mouth and Theresa can be a paranoid control freak.”